android实现底部导航栏

package com.gjn.mynavigation; 
 
import android.os.Bundle; 
import android.support.v4.app.FragmentActivity; 
import android.support.v4.app.FragmentTabHost; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.Window; 
import android.widget.ImageView; 
import android.widget.TabWidget; 
import android.widget.TextView; 
import android.widget.TabHost.OnTabChangeListener; 
import android.widget.TabHost.TabSpec; 
 
public class MainActivity extends FragmentActivity implements OnTabChangeListener { 
 
 private FragmentTabHost mTabHost; 
 @Override 
 protected void onCreate(Bundle savedInstanceState) { 
  super.onCreate(savedInstanceState); 
  requestWindowFeature(Window.FEATURE_NO_TITLE); 
  setContentView(R.layout.activity_main); 
 
  //初始化FragmentTabHost 
  initHost(); 
  //初始化底部导航栏 
  initTab(); 
  //默认选中 
  mTabHost.onTabChanged(TabDb.getTabsTxt()[0]); 
 } 
 
 private void initTab() { 
  String[] tabs = TabDb.getTabsTxt(); 
  for (int i = 0; i < tabs.length; i++) { 
   //新建TabSpec 
   TabSpec tabSpec = mTabHost.newTabSpec(TabDb.getTabsTxt()[i]); 
   //设置view 
   View view = LayoutInflater.from(this).inflate(R.layout.tabs_foot, null); 
   ((TextView) view.findViewById(R.id.foot_tv)).setText(TabDb.getTabsTxt()[i]); 
   ((ImageView) view.findViewById(R.id.foot_iv)).setImageResource(TabDb.getTabsImg()[i]); 
   tabSpec.setIndicator(view); 
   //加入TabSpec 
   mTabHost.addTab(tabSpec,TabDb.getFramgent()[i],null); 
  } 
 } 
 /*** 
 * 初始化Host 
 */ 
 private void initHost() { 
  mTabHost = (FragmentTabHost) findViewById(R.id.main_tab); 
  //调用setup方法 设置view 
  mTabHost.setup(this, getSupportFragmentManager(),R.id.main_view); 
  //去除分割线 
  mTabHost.getTabWidget().setDividerDrawable(null); 
  //监听事件 
  mTabHost.setOnTabChangedListener(this); 
 } 
 
 @Override 
 public void onTabChanged(String arg0) { 
  //从分割线中获得多少个切换界面 
  TabWidget tabw = mTabHost.getTabWidget(); 
  for (int i = 0; i < tabw.getChildCount(); i++) { 
   View v = tabw.getChildAt(i); 
   TextView tv = (TextView) v.findViewById(R.id.foot_tv); 
   ImageView iv = (ImageView) v.findViewById(R.id.foot_iv); 
   //修改当前的界面按钮颜色图片 
   if (i == mTabHost.getCurrentTab()) { 
    tv.setTextColor(getResources().getColor(R.color.tab_light_color)); 
    iv.setImageResource(TabDb.getTabsImgLight()[i]); 
   }else{ 
    tv.setTextColor(getResources().getColor(R.color.tab_color)); 
    iv.setImageResource(TabDb.getTabsImg()[i]); 
   } 
  } 
 } 
} 

package com.gjn.mynavigation; 
 
public class TabDb { 
 /*** 
 * 获得底部所有项 
 */ 
 public static String[] getTabsTxt() { 
  String[] tabs = {"首页","交易","地点","我的"}; 
  return tabs; 
 } 
 /*** 
 * 获得所有碎片 
 */ 
 public static Class[] getFramgent(){ 
  Class[] cls = {OneFm.class,TwoFm.class,ThreeFm.class,FourFm.class}; 
  return cls ; 
 } 
 /*** 
 * 获得所有点击前的图片 
 */ 
 public static int[] getTabsImg(){ 
  int[] img = {R.drawable.home1,R.drawable.glod1,R.drawable.xc1,R.drawable.user1}; 
  return img ; 
 } 
 /*** 
 * 获得所有点击后的图片 
 */ 
 public static int[] getTabsImgLight(){ 
  int[] img = {R.drawable.home2,R.drawable.glod2,R.drawable.xc2,R.drawable.user2}; 
  return img ; 
 } 
} 

package com.gjn.mynavigation; 
 
import java.util.ArrayList; 
import java.util.List; 
 
import android.os.Bundle; 
import android.support.annotation.Nullable; 
import android.support.v4.app.Fragment; 
import android.support.v4.view.ViewPager; 
import android.support.v4.view.ViewPager.OnPageChangeListener; 
import android.util.DisplayMetrics; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.HorizontalScrollView; 
import android.widget.RadioButton; 
import android.widget.RadioGroup; 
import android.widget.RadioGroup.LayoutParams; 
import android.widget.RadioGroup.OnCheckedChangeListener; 
 
public class OneFm extends Fragment implements OnPageChangeListener { 
 
 private View view; 
 private RadioGroup rg_; 
 private ViewPager vp_; 
 private HorizontalScrollView hv_; 
 private List newsList = new ArrayList(); 
 private OneFmAdapter adapter; 
 
 @Override 
 public View onCreateView(LayoutInflater inflater, 
 @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { 
  if (view == null) { 
   //初始化view 
   view = inflater.inflate(R.layout.fm_one, container,false); 
   rg_ = (RadioGroup) view.findViewById(R.id.one_rg); 
   vp_ = (ViewPager) view.findViewById(R.id.one_view); 
   hv_ = (HorizontalScrollView) view.findViewById(R.id.one_hv); 
   //设置RadioGroup点击事件 
   rg_.setOnCheckedChangeListener(new OnCheckedChangeListener() { 
 
    @Override 
    public void onCheckedChanged(RadioGroup group, int id) { 
     vp_.setCurrentItem(id); 
    } 
   } 
   //初始化顶部导航栏 
   initTab(inflater); 
   //初始化viewpager 
   initView(); 
  } 
  /**
  * 底部导航栏切换后 由于没有销毁顶部设置导致如果没有重新设置view 
  * 导致底部切换后切回顶部页面数据会消失等bug 
  * 以下设置每次重新创建view即可 
  */ 
  ViewGroup parent = (ViewGroup) view.getParent(); 
  if (parent != null) { 
   parent.removeView(view); 
  } 
  return view; 
  } 
  /*** 
  * 初始化viewpager 
  */ 
  private void initView() { 
  List hTabs = HTabDb.getSelected(); 
  for (int i = 0; i < hTabs.size(); i++) { 
   OneFm1 fm1 = new OneFm1(); 
   Bundle bundle = new Bundle(); 
   bundle.putString("name", hTabs.get(i).getName()); 
   fm1.setArguments(bundle); 
   newsList.add(fm1); 
  } 
  //设置viewpager适配器 
  adapter = new OneFmAdapter(getActivity().getSupportFragmentManager(),newsList); 
  vp_.setAdapter(adapter); 
  //两个viewpager切换不重新加载 
  vp_.setOffscreenPageLimit(2); 
  //设置默认 
  vp_.setCurrentItem(0); 
  //设置viewpager监听事件 
  vp_.setOnPageChangeListener(this); 
  } 
  /*** 
  * 初始化头部导航栏 
  * @param inflater 
  */ 
  private void initTab(LayoutInflater inflater) { 
  List hTabs = HTabDb.getSelected(); 
  for (int i = 0; i < hTabs.size(); i++) { 
   //设置头部项布局初始化数据 
   RadioButton rbButton = (RadioButton) inflater.inflate(R.layout.tab_rb, null); 
   rbButton.setId(i); 
   rbButton.setText(hTabs.get(i).getName()); 
   LayoutParams params = new LayoutParams(LayoutParams.WRAP_CONTENT, 
   LayoutParams.WRAP_CONTENT); 
   //加入RadioGroup 
   rg_.addView(rbButton,params); 
  } 
  //默认点击 
  rg_.check(0); 
  } 
  @Override 
  public void onPageScrollStateChanged(int arg0) { 
 
  } 
  @Override 
  public void onPageScrolled(int arg0, float arg1, int arg2) { 
 
  } 
  @Override 
  public void onPageSelected(int id) { 
  setTab(id); 
  } 
  /*** 
  * 页面跳转切换头部偏移设置 
  * @param id 
  */ 
  private void setTab(int id) { 
  RadioButton rbButton = (RadioButton) rg_.getChildAt(id); 
  //设置标题被点击 
  rbButton.setChecked(true); 
  //偏移设置 
  int left = rbButton.getLeft(); 
  int width = rbButton.getMeasuredWidth(); 
  DisplayMetrics metrics = new DisplayMetrics(); 
  getActivity().getWindowManager().getDefaultDisplay().getMetrics(metrics); 
  int screenWidth = metrics.widthPixels; 
  //移动距离= 左边的位置 + button宽度的一半 - 屏幕宽度的一半 
  int len = left + width / 2 - screenWidth / 2; 
  //移动 
  hv_.smoothScrollTo(len, 0); 
 } 
} 

package com.gjn.mynavigation; 
 
/*** 
 * 头部Tab属性 
 * 
 */ 
public class HTab { 
 private String name; 
 
 public HTab(String name) { 
  super(); 
  this.setName(name); 
 } 
 
 public String getName() { 
  return name; 
 } 
 
 public void setName(String name) { 
  this.name = name; 
 } 
} 

package com.gjn.mynavigation; 
 
import java.util.ArrayList; 
import java.util.List; 
 
public class HTabDb { 
 private static final List Selected = new ArrayList(); 
 static{ 
  Selected.add(new HTab("今日")); 
  Selected.add(new HTab("头条")); 
  Selected.add(new HTab("娱乐")); 
  Selected.add(new HTab("财经")); 
  Selected.add(new HTab("军事")); 
  Selected.add(new HTab("科技")); 
  Selected.add(new HTab("时尚")); 
  Selected.add(new HTab("体育")); 
 } 
 /*** 
 * 获得头部tab的所有项 
 */ 
 public static List getSelected() { 
  return Selected; 
 } 
} 

package com.gjn.mynavigation; 
 
import android.os.Bundle; 
import android.support.annotation.Nullable; 
import android.support.v4.app.Fragment; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.TextView; 
 
public class OneFm1 extends Fragment { 
 
 private String name; 
 
 @Override 
 public void setArguments(Bundle args) { 
  name = args.getString("name"); 
 } 
 
 @Override 
 public View onCreateView(LayoutInflater inflater, 
 @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { 
  View view = inflater.inflate(R.layout.fragment, container,false); 
  ((TextView) view.findViewById(R.id.fm_text)).setText(name); 
  return view; 
 } 
}